haxe: How to create neat observer pattern prototype

Question

I have created simple observer prototype:

class CObservable<T> {

    public function new() {
        mObservers = new Array<T>();
    }

    public function sign(aObserver:T):Bool {
        for (observer in mObservers)
            if (observer == aObserver)
                return false;
        mObservers.push(aObserver);
        return true;
    }

    private var mObservers:Array<T>;

}

And create interface with some callback functions:

interface IConcreteObserver {

    function onStart(aObservable:CConcreteObservable):Void;

    function onStop(aObservable:CConcreteObservable):Void;

    // ... more callbacks with same signature that differs only by names ...

}

And then I extend prototype with some concrete class:

class CConcreteObservable extends CObservable<IConcreteObserver> {

    public function new() {
        super();
    }

    public function notifyStart():Void {
        for (observer in mObservers)
            observer.onStart(this);
    }

    public function notifyStop():Void {
        for (observer in mObservers)
            observer.onStop(this);
    }

    // ... more notify methods for every callback ...
    // ... more and more ...
    // ... and even more ...

}

All these copy-pastes looks quite impractical for me especially when I have over than a dozen callback methods. Is there any neat trick to declare one simple notify method or may be macro in prototype and call them like notify(onStart), notify(onStop) and so on?